vineet9981
New member
In the diagram shown, an object $O$ is at a distance 10 cm above the water level. Water column in beaker is of 12 cm which is kept on a plane mirror. If refractive index of water is $\mu_w=\frac{4}{3}$ then the distance $D$ behind the mirror where the image $y$ is formed is
(21) A disc is placed on the surface of a water lake of refractive index $\mu$. A fish is at a depth ' $d$ ' below the surface of water. What is the minimum area of the disc so that the fish is. not able to see the world outside the lake?
(1) $\frac{\pi d^2}{\left(\mu^2-1\right)}$
(2) $\pi d^2$
(3) $\frac{\pi d^2}{\mu}$
(4) $\frac{\pi d^2}{(\mu-1)}$
(21) A disc is placed on the surface of a water lake of refractive index $\mu$. A fish is at a depth ' $d$ ' below the surface of water. What is the minimum area of the disc so that the fish is. not able to see the world outside the lake?
(1) $\frac{\pi d^2}{\left(\mu^2-1\right)}$
(2) $\pi d^2$
(3) $\frac{\pi d^2}{\mu}$
(4) $\frac{\pi d^2}{(\mu-1)}$
Attachments
Last edited by a moderator: